Dissipation scale lengths of density turbulence in the inner solar wind

Abstract

Knowing the lengthscales at which turbulent fluctuations dissipate is key to understanding the nature of weakly compressible magnetohydrodynamic turbulence. We use radio wavelength interferometric imaging observations which measure the extent to which distant cosmic sources observed against the inner solar wind are scatter-broadened. We interpret these observations to determine that the dissipation scales of solar wind density turbulence at heliocentric distances of 2.5 -- 20.27 $R_{\odot }$ range from $\approx$ 13500 to 520 m. Our estimates from $\approx$ 10--20 $R_{\odot }$ suggest that the dissipation scale corresponds to the proton gyroradius. They are relevant to in-situ observations to be made by the Parker Solar Probe, and are expected to enhance our understanding of solar wind acceleration.

Accepted for publication in The Astrophysical Journal (8 pages, 4 figures, 1 table)

References in corpus (12)

• Small Scale Energy Cascade of the Solar Wind Turbulence
• Solar wind turbulent spectrum at plasma kinetic scales
• Radial Dependence of the Frequency Break Between Fluid and Kinetic Scales in the Solar Wind Fluctuations
• Multiscale nature of the dissipation range in gyrokinetic simulations of Alfvénic turbulence
• Density Fluctuation Spectrum of Solar Wind Turbulence between Ion and Electron Scales
• Kinetic cascade in solar-wind turbulence: 3D3V hybrid-kinetic simulations with electron inertia
• The structure of solar radio noise storms
• Energy dynamics and current sheet structure in fluid and kinetic simulations of decaying magnetohydrodynamic turbulence
• Spectral breaks of Alfvenic turbulence in a collisionless plasma
• Amplitude of solar wind density turbulence from 10--45 $R_{\odot }$
• Coronal turbulence and the angular broadening of radio sources - the role of the structure function
• Turbulent density fluctuations and proton heating rate in the solar wind from 9-20~R_{\odot}

Cited by in corpus (5)

• Turbulent Proton Heating Rate in the Solar Wind from $5$ to $45R_{\odot }$
• Solar coronal density turbulence and magnetic field strength at the source regions of two successive metric type II radio bursts
• Preparing for Solar and Heliospheric Science with the SKAO: An Indian Perspective
• Ion-scale Turbulence and Energy Cascade Rate in the Solar Corona and Inner Heliosphere
• Observations of shock propagation through turbulent plasma in the solar corona